Code 65 - Vacuum Switch Closed

Ensure that vacuum hoses are connected to switch and engine coolant is between 140-200°F (60-93°C).

1. Turn engine and ignition off and disconnect vacuum switch from vehicle harness. Connect ohmmeter across switch connector (Blk/Lt Grn and Yel/Blk) to measure switch resistance. If resistance is greater than 1000 ohms, reconnect switch. If less than 1000 ohms replace switch assembly.
2. Disconnect vehicle harness from MCU. Connect ohmmeter between MCU connector pin 18 and engine ground. If resistance is greater than 1000 ohms, replace MCU. If less than 1000 ohms, repair circuits.